以其人之道，还治其人之身

yǐ qí rén zhī dào , huán zhì qí rén zhī shēnyiqirenzhidao,huanzhiqirenzhishen

1. to use an opponent's own methods to obtain retribution (idiom, from Song dynasty neo-Confucianist Zhu Xi 朱熹[Zhu1 Xi1])
2. to get revenge by playing sb back at his own game; to give sb a taste of his own medicine

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